diff --git a/crypto/stack/stack.c b/crypto/stack/stack.c
index 286f290c9760b82917c563d3c656811cd5cc10b6..d486f335b2ebec07c9bfef6e2a9890ddfc61a434 100644
--- a/crypto/stack/stack.c
+++ b/crypto/stack/stack.c
@@ -336,7 +336,7 @@ void *sk_set(_STACK *st, int i, void *value)
 
 void sk_sort(_STACK *st)
 {
-    if (st && !st->sorted) {
+    if (st && !st->sorted && st->comp != NULL) {
         int (*comp_func) (const void *, const void *);
 
         /*